Field of the Invention
The present invention relates to a device for gripping a substrate without contact, and more particularly, to a device for gripping a substrate without making contact with the substrate.
Description of Related Art
Glass substrates used for the fabrication of flat panel displays, such as thin film transistor liquid crystal displays (TFT-LCDs), plasma display panels (PDPs) or electroluminescent (EL) devices, are manufactured through the process of converting molten glass that is produced from a glass melting furnace into a flat plate and the process of cutting the flat plate of glass to a preset size before being transported to a machining line where they are machined. In the machining line, glass substrates are cut again to the dimensions of flat panel displays, and four edges of glass substrates are chamfered. Here, the term “chamfering” refers to grinding the edge surfaces that are sharp and have minute cracks.
The substrate-chamfering process of the related art transports glass substrates by holding the glass substrates under the vacuum using a vacuum chuck or gripping the glass substrates using compressed air without making contact therewith.
However, when the vacuum chuck is used, the operation of holding the glass substrates under the vacuum causes minute scratches having the size of 3 μm or less to form on the surface of glass substrates, thereby deteriorating the quality of glass substrates.
In addition, the application of the method of gripping glass substrates using compressed air without making contact therewith has the following problem. When a glass substrate is moved during transportation of the glass substrate since the force of gripping glass substrates in a non-contact state is weak, the glass substrate easily comes into contact with and is damaged by the device for transporting glass substrates without contact. FIG. 1 is a picture showing a scratch formed on a glass substrate by a related-art device for gripping a substrate without contact.
The information disclosed in the Background of the Invention section is provided only for better understanding of the background of the invention, and should not be taken as an acknowledgment or any form of suggestion that this information forms a prior art that would already be known to a person skilled in the art.